. Istanbul 2004 
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vailable in the 
International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B3. Istanbul 2004 
  
  
  
  
  
  
  
  
Figure 4. Convergence of the snake at increasing scale 
The whole process is rapidly convergent. The final result is 
shown below. Comparison with ground truth is currently under 
way. 
  
Figure 5. Snake at original image 
5. CONCLUSION 
We have employed an algorithm which utilizes a modified 
version of the active contour model, using a class of external 
forces defined by the negative of the modulus of wavelet 
transform of the image. The wavelet-based active contour 
model combine wavelet decomposition and edge detection in a 
single procedure. It has been applied to SAR sateilite images to 
determine the coastline. Obtained results are encouraging, and 
further tests are in progress. 
ACKNOWLEDGMENTS 
The work described in the present paper has been funded in 
part through project 23 of CIPE-MIUR CLUSTER 22. 
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